Understand what a file can conceal, inspect it manually, and learn what automated checks can—and cannot—tell you.
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Students and educators
Learn how concealed document content can affect AI tools and academic-integrity reviews, how to inspect a file, and how to document a concern fairly.
Learn how to check a PDF for invisible text, OCR layers, off-page content, annotations, attachments, and text hidden behind shapes.
Check whether black boxes in a PDF are genuine redactions or visual cover-ups that leave sensitive text selectable, searchable, or extractable.
Word
Find hidden formatting, white or tiny text, comments, tracked changes, headers, text boxes, metadata, and embedded content in DOCX files.
Excel
Inspect Excel workbooks for hidden rows, columns, worksheets, very hidden sheets, formulas, names, comments, links, and embedded objects.
Sharing
A safe workflow for reviewing and removing document metadata, comments, revisions, properties, and editing residue before sharing.
Checklist
Use this checklist before submitting or sharing a PDF, Word document, Excel workbook, or text file.
Plain text
Understand zero-width spaces, bidirectional controls, homoglyphs, mixed scripts, and other invisible Unicode characters in text.
Automated inspection can surface evidence that deserves attention, but it cannot determine a person’s intent or guarantee that every hidden element was found. Verify important findings in the source document and preserve the original file when documenting a concern.